Are fans enough

I have 2 fans running inside my 3x6 tent. I did have a small fan heater outside blowing in warmer fresh air as it was winter here. Now that it’s spring the temperature and humidity is perfect with just the lights,fans and humidifier. I have 1 300w and 1 600w led. My question is am I adversely affecting my yields by not having a fresh source of air constantly coming in and just relying on 2 open flaps on the tent on either side the fans to circulate the air in there?, they have only been without fresh air blowing in for the last 2 days and just relying the the open flap and fans

When I had the heater going I didn’t have reverse pressure, the sides of the tent seem to bulge out.

I think I’ll just get a decent ventilation system.

So lemme get this right… u have an exhaust fan n ducting… n 2 fans at the slotted opening for intake? Yes air pressure pulls in fresh air

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im not sure i understand. it sounds like you have a heater outside blowing air toward a vent into your grow and two fans inside only circulating air? idk, you may want one fan blowing air out if you are concerned you arent getting enough fresh air


When the tent is bulged out to the outside you have positive pressure. With the exhaust fan running pulling out stale Hot air. Open pass-through hole at the bottom you should have negative pressure in the tent . You should be able to put your hand on the outside of the pass through hole and feel it pulling fresh air in. At the same time it’s exhausting. Stale air out .Hope that helps good luck


I purchased 2 intake outtake exhaust fans. Until then I’m just using the 2 fans I have, one up in the top 6’ port in reverse venting the hot air and another on the ground blowing fresh air in. It seems to be reverse pressure now. Thanks for the help.


Same sort of set up I do for veg. Intake at the bottom exhaust on top. That works well. I did get a 4 inch inline fan with filter for the flower stage. They will make your whole house smell like weed otherwise. That’s not a bad thing as long as you’re not worried about being discrete.